System and method for current and/or temperature control of light fixture

ABSTRACT

A system for current and/or temperature control of light fixtures includes a sensor in communication with a light fixture, sense a current flow or a temperature of the light fixture, and communicate an input signal relative to the current flow or the temperature; a variable switch in communication with the light fixture to regulate the current flow of the light fixture in response to a control signal; and a controller in communication with the sensor and the variable switch to monitor the input signal, compare the input signal to a condition, and communicate the control signal to the variable switch to control its operation. A bypass circuit applies a normal current directly to the light fixture should a failure occur with the sensor, the variable switch or the controller. A method for current and/or temperature control of light fixtures includes providing the system, monitoring the current flow or the temperature of the light fixture; regulating the current flow of the light fixture, and bypassing the monitoring and regulating should a failure occur in the circuitry.

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation-in-part of U.S. patent applicationSer. No. 11/712,856, entitled “System And Method For Current And/OrTemperature Control Of Light Fixture” and filed Mar. 1, 2007, whichclaims the benefit of priority to U.S. Provisional Patent ApplicationSer. No. 60/840,352, entitled “Wattage or Current Control Circuit Idea,”and filed on Aug. 28, 2006, which is incorporated by reference herein.

TECHNICAL FIELD

This invention relates to light fixtures, and specifically to a systemand method for current and/or temperature control of light fixtures.

BACKGROUND OF INVENTION

Light fixtures have been in use essentially ever since the introductionof electricity as a source of power in buildings and other environments.Modern light fixtures typically include at least a light source (such asa bulb or lamp) and a housing that supports and/or encloses the lightsource and connects it to an electrical power source (e.g., through alight socket and wiring). They may be attached to ceilings, walls, orother parts of a building's structure and may also be combined withother components. For example, the combination of a light fixture and afan fixture (e.g., a ceiling fan) is common, for example, to providefan/light combination fixture.

Typically, light fixtures have some limitations (e.g., due to theirstructure or design) on the amount of current and/or temperature theycan sustain under normal, safe, and/or otherwise desirable operatingconditions. For example, many light fixtures are designed to safelysustain the current and temperature that typically result during theoperation of one or more 60 watt bulbs connected to a 120 volt powersource. Such safe operating limits (also described as ratings) aretypically labeled on the light fixture to inform the user.

However, a light source which operation may cause a higher than ratedcurrent and/or temperature to occur in a light fixture (e.g., a 75 wattbulb for a 60 watt rating) can usually be installed, whetherintentionally (e.g., to obtain more light) or accidentally as anoversight. Such operation of a light fixture with a larger light sourcethan it is rated to handle may result in abnormal, unsafe, or otherwiseundesirable conditions, which can cause a loss of operation andsignificant damage to the light fixture and the surrounding environment,e.g., due to excessive heat, smoke, and/or fire.

Accordingly, it is seen that a need exists for a system and method tocontrol the current and/or temperature of light fixtures to avoid a lossof operation and/or damage that may occur when a larger than rated lightsource is used with them. It is to the provision of such therefore thatthe present invention is primarily directed.

SUMMARY OF INVENTION

The invention, in accordance with exemplary embodiments describedherein, provides a system and method for current and/or temperaturecontrol of light fixtures. An exemplary system of the invention caninclude a sensor structured to be in communication with a light fixture,sense a current flow or temperature of the light fixture, andcommunicate an input signal relative to the current flow or temperature;a variable switch structured to be in communication with the lightfixture and regulate the current flow of the light fixture in responseto a control signal; and a controller in communication with the sensorand the variable switch and structured to monitor the input signalcommunicated by the sensor, compare the input signal to a condition, andcommunicate the control signal to the variable switch to control itsoperation.

An exemplary method of the invention can include providing the foregoingexemplary system for current and/or temperature control of lightfixtures; monitoring the current flow or temperature of the lightfixture via communication of the input signal from the sensor to thecontroller; and regulating the current flow of the light fixture inresponse to the controller determining that the input signal meets thecondition via the controller communicating the control signal to thevariable switch.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a block diagram of a system for current and/or temperaturecontrol of light fixtures.

FIG. 2 is a diagram of a first exemplary circuit for the system forcurrent and/or temperature control of light fixtures shown in FIG. 1.

FIG. 3 is a diagram of a second exemplary circuit for the system forcurrent and/or temperature control of light fixtures shown in FIG. 1.

FIG. 4 is a diagram of a third exemplary circuit for the system forcurrent and/or temperature control of light fixtures shown in FIG. 1.

FIG. 5 is a flowchart diagram of a method for current and/or temperaturecontrol of light fixtures.

FIG. 6 is a flowchart diagram of a first sub-method of the method forcurrent and/or temperature control of light fixtures shown in FIG. 5.

FIG. 7 is a flowchart diagram of a second sub-method of the method forcurrent and/or temperature control of light fixtures shown in FIG. 5.

FIG. 8 is a flowchart diagram of a third sub-method of the method forcurrent and/or temperature control of light fixtures shown in FIG. 5.

FIG. 9 is a block diagram of a fourth exemplary of a system for currentand/or temperature control of light fixtures.

FIG. 10 is a diagram of the system for current and/or temperaturecontrol of light fixtures shown in FIG. 9.

DETAILED DESCRIPTION

With reference next to the drawings, FIG. 1 shows a block diagram of asystem 100 for current and/or temperature control of light fixtures. Thesystem 100 may be in communication with and/or integrated within a lightfixture circuit 150. The system 100 includes a sensor 110 that istypically configured (structured, designed, etc.) to sense (measure,monitor, detect, etc.) one or more characteristics (conditions,parameters, etc.) of the light fixture circuit 150 and/or the lightfixture (not depicted) and communicate information relative to thesensed characteristics (e.g., magnitude, frequency, etc.) to otherdevices or elements. For example, the sensor 110 may be structured tosense a current flow through or about one or more portions of the lightfixture circuit 150, such as the depicted current flow 155, andcommunicate information relative to the current flow (e.g., magnitude,amount, etc.) to another device or element of the system 100. As anotherexample, the sensor 110 may be structured to sense a temperature of orabout one or more portions of the light fixture circuit 150 and/or thelight fixture, such as the depicted temperature 165 in the vicinity ofthe load 160, and communicate information relative to the temperature toanother device or element of the system 100. The sensor 110 may beconfigured to sense other characteristics of the light fixture circuit150 or light fixture and communicate relative information thereof, whichwill be apparent in light of the disclosure herein.

The system 100 also includes a variable switch 120 that is configured toswitch (e.g., on and/or off) one or more operating characteristics ofthe light fixture circuit 150. For example, the variable switch 120 maybe configured to switch on or off the current flow 155 through the lightfixture circuit 150. Moreover, the variable switch 120 may be configuredto switch the current flow 155 or other operating characteristics on andoff at a some cycle and/or frequency to affect the overall nature of theoperating characteristic and in effect regulate the operatingcharacteristic. For example, with respect to the current flow 155, thevariable switch 120 may be structured to switch it on and off at acyclical frequency that in effect modifies (e.g., decreases, increases,etc.) the resultant current flow 155 through one or more portions of thelight fixture circuit 150, such as through the load 160. This featurewill be appreciated, for example, with respect to modifying themagnitude of an alternating current (AC) operating characteristic.Moreover, it will be apparent based on the disclosure herein that thevariable switch 120 may be structured to switch other operatingcharacteristics of the light fixture circuit 150 and to switch in otherways (i.e., besides on/off, cyclical frequency, etc.).

The system 100 further includes a controller 130 that are typically incommunication with the sensor 110 and variable switch 120 as depicted inFIG. 1. The controller 130 is typically configured to monitor and/orcontrol the operation of one or more components in communication withthe controller 130, such as the sensor 110 and variable switch 120. Forexample, the controller 130 may monitor one or more inputs (e.g.,signals such as currents, voltages, etc.) received from the sensor 110.As another example, the controller 130 may control the operation of thevariable switch 120 by one or more outputs (e.g., signals such ascurrents, voltages, etc.) sent to the variable switch 120. It will beapparent that the controller 130 can be configured to monitor or controlother components (devices, systems, etc.), such as other components ofthe light fixture circuit 150.

The foregoing elements of the system 100, namely the sensor 110,variable switch 120, and controller 130, can be made (formed,manufactured, etc.) of one or more of numerous materials and/orcomponents by one or more of numerous methods or processes, which willbe apparent in light of the disclosure herein. For example, the sensor110, variable switch 120, and/or controller 130 may include one or moreelectrical components (such as conductors, resistors, capacitors,transformers, etc.), electronic components (such as transistors,semiconductors, integrated circuits, chips, circuit boards, etc.),computing components (such as electronic logic, programmable logic,microprocessors, computing processors, etc.), etc. Several examples ofsuch components which the sensor 110, variable switch 120, and/orcontroller 130 may include will be discussed below with respect to FIGS.2-4. Furthermore, some examples of the operation of one or more of theseelements of the system 100 will be discussed below with respect to FIGS.5-8. It is also noted that elements of the system 100, such as thesensor 110, variable switch 120, and controller 130 may be separatecomponents or integrated in various combinations, which will be apparentin light of the disclosure herein.

As mentioned above, the system 100 may be in communication with and/orintegrated within a light fixture circuit 150. This light fixturecircuit 150 may include various components, but typically includes atleast a load 160 and may further include a conditioner 170 as depictedin FIG. 1. The load 160 typically includes a light source such as a lampor light bulb, which can be utilized to provide light from a lightingfixture mounted. The conditioner 170 typically includes an inductor,capacitor, and/or other such components or equivalents thereof, whichcan provide filtering or other conditioning of various characteristics(e.g., undesirable) that exist in the light fixture circuit 150. Forexample, the conditioner 170 may filter or otherwise conditioninterference or other undesirable characteristics resulting from theoperation of the load 160 or of one or more components of the system100, such as the variable switch 120. The inclusion and use of the load160, conditioner 170, and/or other components within the light fixturecircuit 150 will be apparent in light of the disclosure herein, as willbe the possible compositions and methods or processes of making suchcomponents.

FIG. 2 shows a diagram of a first exemplary circuit 200 for the system100 for current and/or temperature control of light fixtures shown inFIG. 1. Similar to the system 100 of FIG. 1, the exemplary circuit 200may be in communication with and/or integrated within a light fixturecircuit 250. The circuit 200 may include a current sensor 212 that isconfigured to sense a current flow 255 through the light fixture circuit250. As will be appreciated in light of the disclosure herein, thecurrent sensor 212 may include one or more of numerous elements(components, devices, etc.). For example, the current sensor 212 mayinclude a current transformer in communication with (e.g., connected to,in proximity therewith, etc.) the light fixture circuit 250 and alsowith the controller 230 so that the current sensor 212 can sense thecurrent flow 255 and communicate characteristics of it (e.g., magnitude,polarity, etc.) to the controller 230 (e.g., via a signal such as acurrent, voltage, etc.). As another example, the current sensor 212 mayinclude a transducer that is configured to sense the current flow 255and communicate characteristics of it to the controller 230.

The circuit 200 may also include a temperature sensor 216 that isconfigured to sense a temperature of or about one or more portions ofthe light fixture circuit 250 or light fixture, such as the temperatureof or in the vicinity of the light source 260 (discussed below). As willbe appreciated in light of the disclosure herein, the temperature sensor216 may also include one or more of numerous elements. For example, thetemperature sensor 216 may include a thermal resistive device (orthermistor, as depicted in FIG. 2) in communication with the lightfixture circuit 250 and/or light fixture and also with the controller230 so that the temperature sensor 216 can sense the temperature andcommunicate characteristics of it (e.g., magnitude, variation, etc.) tothe controller 230 (e.g., via a signal such as a current, voltage,etc.). As another example, the temperature sensor 216 may include atransducer that is configured to sense the temperature of or about oneor more portions of the light fixture circuit 250 and/or light fixtureand communicate characteristics of it to the controller 230.

The current sensor 212 and the temperature sensor 216 are examples ofthe sensor 110 discussed above for FIG. 1. It should be understood andwill be apparent based on the disclosure herein that either the currentsensor 212, the temperature sensor 216, or both sensors 212, 216 can beincluded and/or utilized in the circuit 200. Thus, some embodiments ofthe invention may include the current sensor 212, other embodiments mayinclude the temperature sensor 216, and yet other embodiments mayinclude both the current sensor 212 and the temperature sensor 216 asdepicted for example in FIG. 2.

The circuit 200 also includes a triac 222 that is an example of thevariable switch 120 discussed above for FIG. 1 and is configured toswitch the current flow 255 on and off at a cyclical frequency to modifythe current flow 255 that passes through the light source 260 and/orother elements of the light fixture circuit 250. Triacs are known in theart, including how to make and use them with respect to embodiments ofthe invention. Thus, as known in the art, the triac 222 includes twomain terminals, which are connected to the light fixture circuit 250 andcan allow the current flow 255 to pass through, and a gate terminal,which is connected to the controller 230 to receive signals that affectthe operation of the triac 222 with respect to the current flow 255.

As mentioned above, the circuit 200 also includes a controller 230 thatis in communication with the current sensor 212 and/or temperaturesensor 216 (depending if one or both are included in the circuit 200 asdiscussed above) and with the triac 222. In some embodiments, thecontroller 230 may also be in communication with a remote control 235 asdiscussed below. The controller 230 is an example of the controller 130discussed above for FIG. 1. The controller 230 is configured to receivesignals from the current sensor 212 and/or temperature sensor 216 and,depending on the nature (e.g., magnitude, frequency, variation, etc.) ofthose input signals, to control the operation of the triac 222 bysending output signals to the gate terminal of the triac 222. Thus, thecontroller 230 may be said to trigger the triac 222 (as known in theart) depending on the inputs received from the current sensor 212 and/ortemperature sensor 216. In some embodiments of the invention, thecontroller 230 may also control other characteristics that affect thelight fixture circuit 250, such as switching on or off the feed to thelight fixture circuit 250 from a power source (not depicted) ormodifying the brightness of the light source 260 (e.g., as a dimmercontrol). It will be apparent based on the disclosure herein that thecontroller 230 (similar to the controller 130) may include one or moreof numerous components that provide such configurations and functions,such as one or more electrical components, electronic components,computing components, etc. (some examples of which were presented abovewith respect to FIG. 1). In that regard, some examples of the operation(function, processing, etc.) of the controller 230 will be furtherdiscussed below with respect to FIGS. 5-8. Some specific examples ofcomponents of the controller 230 may include the Samsung S3C9454 8-bitgeneral purpose controller or the OKI MSM64164C 4-bit micro-controllerunit. It will also be apparent that the combination of one or morecomponents of the controller 230 along with the triac 222 may form asystem that is similar to a light dimmer control or dimmer switch.Moreover, the triac 222 may alternatively be another type ofsemi-conducting switch device, which are known in the art.

As previously mentioned, there may also be a remote control 235 incommunication with the controller 230. As known in the art, the remotecontrol 235 can allow a user to remotely transmit signals to thecontroller 230 (e.g., wirelessly via radio frequency signals) that mayaffect the operation of the controller 230 and thereby other componentsof the circuit 200, such as the triac 222. In that regard, the remotecontrol 235 may be used, for example through operation of the controller230, to turn the light source 260 on or off or to modify the brightnessof the light source 260 (e.g., as a dimmer). Other operations that maybe controlled using the remote control 235 will be apparent in light ofthe disclosure herein.

As also mentioned above, the circuit 200 may be in communication withand/or integrated within a light fixture circuit 250. This light fixturecircuit 250 can include a light source 260, which is an example of aload 160 as discussed for FIG. 1. As known in the art, the light source260 can be a light bulb, lamp, or other element that outputs some formof energy (e.g., visible light) when the current flow 255 passes throughit. The light fixture circuit 250 can also include an inductor or RFcoil 270, which is an example of a conditioner 170 as discussed forFIG. 1. As known in the art, the RF coil 270 can filter out undesirablecharacteristics of the current flow 255, the voltage (not depicted), orother signals within the light fixture circuit 250. As also known, suchundesirable characteristics may include interference (e.g., radio,harmonic, etc.) caused by the one or more elements in communication withthe light fixture circuit 250, such as the triac 222, which may causeundesirable operation of the light source 260 (e.g., flicker, unintendeddimming, etc.).

FIG. 3 shows a diagram of a second exemplary circuit 300 for the system100 for current and/or temperature control of light fixtures shown inFIG. 1. Similar to the system 100 of FIG. 1, the exemplary circuit 300may be in communication with and/or integrated within a light fixturecircuit 350. Similar to the circuit 200 of FIG. 2, the circuit 300 mayinclude a current sensor 212 and alternatively or additionally include atemperature sensor 216, which were discussed above with respect to FIG.2. The circuit 300 also includes a triac 222, which was also discussedabove for FIG. 2.

The circuit 300 further includes a controller 330, which is similar tothe controller 230 discussed above for FIG. 2, but also includes a relay332, which may be integrated or separate (as depicted) from thecontroller 330. As depicted in FIG. 3, the controller 330 may be incommunication with the current sensor 212 and/or temperature sensor 216and also in communication with the triac 222, the relay 332, and, insome embodiments, a remote control 235, which was also discussed abovefor FIG. 2. As also depicted, the relay 332 can include a switch(contact, terminal, etc.) that can direct the current flow 355 throughone of at least two paths 1, 2 when the relay is operated. Relays areknown in the art, including how to make and use them with respect toembodiments of the invention.

The addition of the relay 332 to the controller 330 allows the triac 222to be bypassed through additional circuitry 380 that may be includedwith the light fixture circuit 350. This additional circuitry 380 mayinclude a direct path (e.g., short circuit) to the light source 260 oranother circuit (device, system, etc.) that may affect the operation ofthe light source, such as a dimmer circuit (not depicted). By providinga bypass of the triac 222, the relay allows such additional circuitry380 to be used while avoiding interference or other undesirablecharacteristics that may occur if the triac 222 and the additionalcircuitry 380 were connected or otherwise operated together. Forexample, if the additional circuitry 380 is a dimmer that also includesa triac and RF coil, it is known in the art that the operation of suchadditional circuitry 380 in connection with the triac 222, as well asthe RF coil 270, may cause undesirable operation of the light source 260and/or other components of the circuit 300 or light fixture circuit 350.Some examples of the operation of the controller 330 and relay 332 willbe further discussed below with respect to FIGS. 5-8.

The light fixture circuit 350, which the circuit 300 may be incommunication with and/or integrated within, can include a light source260 and RF coil 270 similar to the light fixture circuit 250 of FIG. 2.Details of the light source 260 and RF coil 270 were discussed abovewith respect to FIG. 2. As depicted in FIG. 3, the RF coil 270 (e.g.,along with the triac 222) can be switched out of the light fixturecircuit 350 (e.g., bypassed) by the relay 332 in some embodiments of theinvention as discussed above.

FIG. 4 shows a diagram of a third exemplary circuit 400 for the system100 for current and/or temperature control of light fixtures shown inFIG. 1. Similar to the system 100 of FIG. 1, the exemplary circuit 400may be in communication with and/or integrated within a light fixturecircuit 450. The circuit 400 is similar to the circuit 300 of FIG. 3 andincludes a current sensor 212 and/or temperature sensor 216 and a relay332, which were described above for FIG. 3. The circuit 400 alsoincludes a controller 430 that is similar to the controller 330described above except that it is not in communication with a triac.Some examples of the operation of the controller 430 and relay 332 willbe further discussed below with respect to FIGS. 5-8.

Instead of a triac, the circuit 400 includes a diode 422, which isanother example of the variable switch 120 of FIG. 1. Diodes are knownin the art, including how to make and use them with respect toembodiments of the invention. Therefore, it will be apparent in light ofthe disclosure herein that the diode 422 can vary the current flow 455(e.g., between full flow and no flow) when it is switched into operationby the relay 332 resulting in a current flow 455 through the lightsource 260 that is, for example, approximately half of the originalcurrent flow 455 in the light fixture circuit 450.

Similar to the light fixture circuit 350 of FIG. 3, the light fixturecircuit 450 can include a light source 260 and RF coil 270. Furthermore,one path 1 of the relay 332 may be in communication with additionalcircuitry 380 as depicted, which may be included in the light fixturecircuit 450. The light source 260, RF coil 270, and additional circuitry380 were described above, for example, with respect to FIG. 3.

It is noted with respect to the foregoing discussion of FIGS. 1-4 thatvarious systems and/or circuits were described that included elements invarious positions relative to each other. However, it should beunderstood and apparent in light of the disclosure herein that suchdescribed elements (as well as other elements) may be positionedalternatively in numerous variations within the scope of the invention.It should also be understood that the term light fixture as used hereinmay refer to a system (structure, device, etc.) that includes a lightfixture circuit or that the two terms may be used interchangeably torefer to an overall system or portions thereof, such as a circuitportion.

The following description of exemplary embodiments of the invention withrespect to FIGS. 5-8 may include exemplary references to elementsdiscussed above with respect to FIGS. 1-5 as applicable to facilitatethe description. However, it should be understood that such referencesare exemplary and not limiting with respect to the scope of exemplaryembodiments of the invention. Furthermore, it should be understood thatsome steps of the exemplary methods (sub-methods, processes, etc.)described below may be performed before or after other steps of themethods (respectively), or in parallel or combination with other steps,without departing from the scope of exemplary embodiments of theinvention.

FIG. 5 shows a flowchart diagram of a method 500 for current and/ortemperature control of light fixtures. This method may be performed, forexample, by the controller 130 and/or other elements of the system 100,which were discussed above for FIG. 1. The method 500 begins with step502 in which the controller 130 monitor one or more characteristics ofthe light fixture circuit 150 and/or light fixture via one or moreinputs from the sensor 110. The method proceeds to step 504 in which thecontroller 130 determine whether one or more of the monitoredcharacteristics meets a corresponding condition. For example, thecontroller 130 may be configured to compare the input(s) from the sensor110 to one or more predetermined values to determine if the input(s)meet a predetermined comparison condition (e.g., less than, equal,greater than, etc.).

If a corresponding condition is not met in step 504, the method proceedsto step 506 in which the controller 130 respond by sending one or moreoutputs to the variable switch 120 to cause it to permit a normal and/orexisting current flow 155 to the load 160. The method then proceeds fromstep 506 back to step 502. However, if a corresponding condition is metin step 504, the method proceeds to step 508 in which the controller 130respond by sending one or more outputs to the variable switch 120 tocause it to modify (e.g., decrease, increase, etc.) the current flow 155to the load 160. As discussed below, the modification of the currentflow 155 may be performed according to a desired procedure. The methodthen proceeds from step 508 back to step 502.

FIG. 6 shows a flowchart diagram of a first sub-method 600 of the method500 for current and/or temperature control of light fixtures shown inFIG. 5. This sub-method 600 may be performed, for example, by thecontroller 230 and/or other elements of the circuit 200, which werediscussed above for FIG. 2. The sub-method 600 begins with step 602 inwhich the controller 230 monitors the current flow 255 via one or moreinputs from the current sensor 212 and/or monitors the temperature(e.g., of or about one or more portions of the light fixture circuit 250or light fixture) via one or more inputs from the temperature sensor 216depending on if either one or both the sensors are included in thecircuit 200.

The sub-method 600 proceeds to step 604 in which the controller 230determines whether the monitored current is greater than a desired(e.g., predetermined, preset, etc.) level or determines whether themonitored temperature is greater than a desired level. If in step 604the monitored current is not greater than the desired level or themonitored temperature is not greater than the desired level, thesub-method 600 proceeds to step 606 in which the controller 230 sendsone or more outputs to the triac 222 to keep the triac 222 “on” andpermit a normal (existing, desired, etc.) current flow 255 to the lightsource 260. For example, it is known in the art that a triac willconduct current once a sufficient (e.g., bias) voltage is applied to itsgate terminal until the current drops below a threshold value.Therefore, in step 606, the controller 230 may apply such bias voltageto the gate terminal of the triac 222 cyclically as frequently aspossible (e.g., at or about the 60 cycle per second frequency of atypical alternating current power source) so that the triac 222 conductsthe current flow 255 as if it were essentially a closed switch or shortcircuit (e.g., there may be some interruption of the flow as the currentdrops below the threshold value while changing polarities). Thesub-method 600 then proceeds from step 606 back to step 602.

However, if in step 604 the monitored current is greater than thedesired level or the monitored temperature is greater than the desiredlevel, the sub-method 600 proceeds to step 608 in which the controller230 sends one or more outputs to the triac 222 to switch the triac 222“on” and “off” cyclically to lower (reduce, decrease, etc.) the currentflow 255 to the light source 260 in accordance with a desired procedure,examples of which are discussed below. For example, according to thesame principle of operation of the triac 222 as described above, thecontroller 230 may apply a bias voltage to the gate terminal of thetriac 222 cyclically at a slower frequency so that the triac 222 cyclesbetween conducting current and not conducting current therebyeffectively reducing the current flow 255 that travels to the lightssource 260. The sub-method 600 then proceeds from step 608 back to step602.

The controller 230 may perform such controlling (operations, functions,etc.) as described above for steps 602, 604, 606, 608 by numerousmethods (processes, steps, etc.) depending on the elements included toconfigure the controller 230, which will be apparent based on thedisclosure herein. For example, if the controller 230 is configured toinclude programmable logic, it may be programmed to perform suchoperations accordingly.

As mentioned above, the controller 230 may cause the triac 222 tooperate to lower the current flow 255 according to a desired procedure(routine, protocol, etc.). One example of such a desired procedure isfor the controller 230 to cause the triac 222 to reduce the current flow255 by a predetermined (preset, precalculated, fixed, etc.) amount(e.g., a percentage such as 25%, 50%, 75%, etc.). Another example ofsuch a desired procedure is for the controller 230 to cause the triac222 to reduce the current flow 255 to a predetermined amount (e.g., 1amp, 2 amps, etc.). Yet another example of such a desired procedure isfor the controller 230 to cause the triac 222 to reduce the current flow255 in order to maintain the temperature (e.g., of or about one or moreportions of the light fixture circuit 250 or light fixture) below acertain maximum (e.g., less than 90 degrees Celsius). Such procedures asthe foregoing may include the controller maintaining and/or modifyingthe operation of the triac 222 dependent on the resultant current flow255 that is sensed by the current sensor 212 and/or on the resultanttemperature that is sensed by the temperature sensor 216. Furthermore,other such desired procedures to reduce the current flow 255 may beperformed by the controller, which will be apparent based on thedisclosure herein.

FIG. 7 shows a flowchart diagram of a second sub-method 700 of themethod 500 for current and/or temperature control of light fixturesshown in FIG. 5. This sub-method 700 may be performed, for example, bythe controller 330 and/or other elements of the circuit 300, which werediscussed above for FIG. 3. The steps 702, 704 of the sub-method 700 areessentially the same as steps 602, 604 of the sub-method 600 describedabove. In step 706 of the sub-method 700 (which is reached if themonitored current is not greater than the desired level or the monitoredtemperature is not greater than the desired level in step 704), thecontroller 330 sends one or more outputs to the relay 332 to cause it toswitch the current flow 355 through path 1 to the light source 260 viathe additional circuitry 380. During this step 706, the controller 330may or may not also send one or more outputs to the triac 222, since itis bypassed from the light fixture circuit 350 via the relay 332 andadditional circuitry 380. The sub-method 700 then proceeds from step 706back to step 702.

In step 708 of the sub-method 700 (which is reached if the monitoredcurrent is greater than the desired level or the monitored temperatureis greater than the desired level in step 704), the controller 330 sendsone or more outputs to the relay 332 to cause it to switch the currentflow 355 through path 2 to the light source 260 via the triac 222. Alsoduring this step 706, the controller 330 sends one or more outputs tothe triac 222 to switch the triac 222 “on” and “off” cyclically to lowerthe current flow 355 to the light source 260 in accordance with adesired procedure similar to as described above for step 608. Thesub-method 700 then proceeds from step 708 back to step 702.

FIG. 8 shows a flowchart diagram of a third sub-method 800 of the method500 for current and/or temperature control of light fixtures shown inFIG. 5. This sub-method 800 may be performed, for example, by thecontroller 430 and/or other elements of the circuit 400, which werediscussed above for FIG. 4. The steps 802, 804, 806 of the sub-method800 are essentially the same as steps 702, 704, 706 of the sub-method700 described above. In step 808 of the sub-method 800 (which is reachedif the monitored current is greater than the desired level or themonitored temperature is greater than the desired level in step 804),the controller 330 sends one or more outputs to the relay 332 to causeit to switch the current flow 455 through path 2 to the light source 260via the diode 422. As discussed above, the diode 422 can reduce thecurrent flow 455, for example, to approximately half of the previouscurrent flow 455 in the light fixture circuit 450. The sub-method 800then proceeds from step 808 back to step 802.

FIGS. 9 and 10 show a diagram of a fourth exemplary circuit 900 for thesystem 100 for current and/or temperature control of light fixtures.Similar to the system 100 of FIG. 1, the exemplary circuit 900 may be incommunication with and/or integrated within a light fixture circuit 350.Similar to the circuit 200 of FIG. 2, the circuit 900 may include acurrent sensor or current sensing circuit 912 and alternatively oradditionally include a temperature sensor, which were discussed abovewith respect to FIG. 2. The circuit 900 also includes a bypass drivercircuit or bypass 920 which is used to switch to a normal light controloperation upon the limiting controller circuit failing wherein normaloperation consists of the lights being at the full power dissipation, asdescribed in more detail hereinafter.

To insure that the light limiter controller function will not impededlighting in a specific environment due to a subcircuit failure, afail-safe mechanism or subcircuit is utilized. Should a limitingcontroller subcircuit failure occur, the environment load or lightsoperate normally, i.e., the lights are illuminated to full intensitywithout the circuit reducing the current.

FIG. 10 shows a detail of circuit 900 including bypass 920. In use, uponthe circuit 900 being energized with an active neutral and line circuitfrom a conventional power source, the controller 930 provides a controlcommand signal (0V) to switch a PNP type transistor 932 and NPN typetransistor 933 “on”. The collector of transistor 933 is at a lowervoltage potential of 24 VDC supplied by a zener diode 935. The coil ofthe electromechanical relay 937 is energized (turned “on”) to allow theelectrical contacts of the electromechanical relay 937 to switch from NC(normally closed) to NO (normally open), thereby connecting the lightbulb 960 to the triad light bulb driver anode pin 938.

A parallel capacitor 941 provides transient suppression of the 60 Hz lowfrequency line voltage coming from the line and neutral circuit wiresattached to the controllers power supply through capacitor 944, varistor945, capacitor 946, diode 947 and diode 948. Zener diode 935 providesthe appropriate voltage rail of 6 VDC for transistor 932 to operateproperly.

With this electrical connection established, the controller 930electrically monitors and regulates the amount of current that flowsthrough the filaments of various watt rated incandescent light bulbs. Ifa maximum current of 2.5 A (0.190 W) (for example) is sensed by thesensing subcircuit, the electrical connection established by relay 937switching contacts provides an appropriate dimming control signal drivenby the triac light bulb driver subcircuit. At this point, the wiredincandescent light bulbs intensity will be commanded to be full bright.If there is either an open or short circuit condition attributed toaging or failed electronic components and/or circuit board trace(s)deterioration, the controller provides either a +5V signal or a Hi Z(impedance) load to a resistor 950, thereby commanding transistor 932and 933 to switch “off”. The voltage potential at the low side of relay937/transistor 933 collector circuit will be equivalent to the 24 VDCpower supply source provided by the zener diode 935, therebyde-energizing (turning “off”) the electromechanical relay's coil. Thesingle pole single throw electrical contacts are then switched from NOto NC. The electrically wired incandescent light bulb 960 load will thenbe disconnected from the trial light bulb driver subcircuit. Theelectrical ground is then connected to the light bulb therebyestablishing a closed electrical circuit turning it “on” at fullintensity with a normal current. The term normal current is intend torepresent a current that is not altered, reduced, modified, or otherwisechanged to substantially reduce the current, as for dimming purposes. Ofcourse, some internal resistance may occur as well as other currentchanges as a result of the electrical components utilized in thecircuitry, especially the bypass circuitry. However, these small changesin the current do not substantially change the current and as such thecurrent is still intended to equate a normal current or a currentwithout regulatory decreasing.

It should be understood that the bypass circuit or other bypass circuitmay be utilized with any of the embodiments shown herein as well asequivalent circuits.

It is thus seen that a system and method to control the current and/ortemperature of light fixtures is now provided to avoid a loss ofoperation and/or damage that may occur when a larger than rated lightsource is used with them, but that also bypasses the dimming operationof the circuit should a failure occur. It should be understood that theforegoing descriptions merely relate to exemplary, illustrativeembodiments of the invention. Furthermore, various elements of thedescribed exemplary embodiments may be known in the art or recognized byone of ordinary skill in the art based on the disclosure herein.Therefore, it should also be understood that various modifications maybe made to exemplary embodiments described herein that are within thespirit and scope of the invention as set forth in the following claims.

1. A system for current and/or temperature control of light fixtures, comprising: a sensor structured to be in communication with a light fixture, to sense a current flow or a temperature of the light fixture, and to communicate an input signal relative to the current flow or temperature; a variable switch structured to be in communication with the light fixture and regulate the current flow of the light fixture in response to a control signal; a controller in communication with the sensor and the variable switch and structured to monitor the input signal communicated by the sensor, to compare the input signal to a condition, and to communicate the control signal to the variable switch to control its operation, and a bypass circuit structured to apply a normal current to the light fixture should a failure occur with said sensor, said variable switch or said controller.
 2. The system of claim 1, wherein the sensor comprises at least one of a current transformer, a thermistor, or a transducer.
 3. The system of claim 1, wherein the condition is one of a predetermined current parameter or a predetermined temperature parameter.
 4. The system of claim 1, wherein the variable switch comprises at least one of a triac, a diode, or a semi-conducting switch device.
 5. The system of claim 1, wherein the variable switch and at least a portion of the controller comprise a dimmer circuit.
 6. The system of claim 1, wherein the controller comprises at least one of a conductor, a resistor, a capacitor, a transformer, a transistor, a semiconductor, an integrated circuit, a chip, a circuit board, an electronic logic, a programmable logic, a microprocessor, or a computing processor.
 7. The system of claim 1, wherein the controller is further structured to be in communication with and at least partially operated via a remote control.
 8. The system of claim 1, wherein the controller is further structured to be in communication with the light fixture and to switch the current flow within the light fixture circuit between at least two paths, wherein one path is in communication with the variable switch.
 9. The system of claim 1, further comprising a relay in communication with the controller and structured to be in communication with the light fixture and to switch the current flow within the light fixture circuit between at least two paths in response to a signal communicated from the controller, wherein one of the paths is in communication with the variable switch.
 10. A method for current and/or temperature control of light fixtures, comprising: providing a sensor structured to be in communication with a light fixture, to sense a current flow or a temperature of the light fixture, and to communicate an input signal relative to the sensed current flow or temperature; providing a variable switch structured to be in communication with the light fixture and regulate the current flow of the light fixture in response to a control signal; providing a controller in communication with the sensor and the variable switch and structured to monitor the input signal communicated by the sensor, to compare the input signal to a condition, and to communicate the control signal to the variable switch to control its operation; monitoring the current flow or the temperature of the light fixture via communication of the input signal from the sensor to the controller; regulating the current flow of the light fixture in response to the controller determining that the input signal meets the condition via the controller communicating the control signal to the variable switch, the regulating including a bypass mode should a malfunction occur with the sensor, controller, or monitoring of the current flow, the bypass mode applying a normal current to the light fixtures without regulatory decreasing the current.
 11. The method of claim 10, wherein regulating the current flow comprises regulating the current flow of the light fixture in response to the controller determining that the input signal meets one of a condition of equaling or exceeding a predetermined current parameter or a condition of equaling or exceeding a predetermined temperature parameter.
 12. The method of claim 10, wherein regulating the current flow comprises maintaining or reducing the current flow of the light fixture via the controller communicating the control signal to the variable switch.
 13. The method of claim 10, wherein regulating the current flow comprises reducing the current flow according to a predetermined procedure comprising one of reducing it by a predetermined amount or reducing it to a predetermined amount.
 14. The method of claim 10, wherein regulating the current flow comprises communicating the control signal to a dimmer circuit comprised of the variable switch and at least a portion of the controller.
 15. A system for current and/or temperature control of light fixtures, comprising: sensor means for sensing the current flow or temperature of a light fixture and to communicate an input signal relative to the current flow or temperature; controller means for controlling the current flow in response to the input signal received from the sensor means, the controller means reducing the current in response to an overload input signal, the controller means also including a bypass for directing a normal current to the light fixture should a failure occur with the controller means.
 16. The system of claim 15 wherein the controller means includes a variable switch structured to be in communication with the light fixture and regulate the current flow of the light fixture in response to a control signal.
 17. The system of claim 16 wherein the controller means includes a controller in communication with the sensor and the variable switch and structured to monitor the input signal communicated by the sensor, to compare the input signal to a condition, and to communicate the control signal to the variable switch to control its operation.
 18. The system of claim 17 wherein the bypass is structured to apply a normal current to the light fixture should a failure occur with said sensor, said variable switch or said controller.
 19. The system of claim 15, wherein the sensor comprises at least one of a current transformer, a thermistor, or a transducer.
 20. The system of claim 16, wherein the variable switch comprises at least one of a triac, a diode, or a semi-conducting switch device.
 21. The system of claim 17, wherein the variable switch and at least a portion of the controller comprise a dimmer circuit. 